(12th shahr of 25). The most pressing threat to Iran from the Alan and Hun nomads came from the Caspian route. Shapur I's province-list therefore separates the Caspian shore from the subject kingdom of Ar(r)an (Parthian Ardan; Albania). It formed the province Balasagan, which extended from Gilan to the Caspian/Albanian/Chol Gates at Darband. It presumably included the lower Araxes plain. Groups of Alans probably settled in this area, e.g., those repulsed from Armenia in 335-6. The increasing numbers of Huns settled around the Gates in the 5th century somewhat eroded Sasanian control; but Kavad reaffirmed it [Procopius, Wars 1.10.1-16]. His wall and foundation of Peroz-Kavad in Shirvan prepared for Khusrau I's massive fortification of Darband (Bab al-Abwab). To secure his barrier across the coastal plain, Khusrau may have transported some tribes here, besides using local ones. Thus the hereditary commanders he appointed at the wall bore such titles as Shirvanshah, Alanshah, Filanshah, Baghranshah. Kavad and Khusrau also strengthened other defenses agaisnt the Huns. To Kavad is attributed the foundation of Bailaqan and Barda'a, the major Albanian cities on the road to Iberia from Ardabil (via Barzand and Warthan). Near Bailaqan, Khusrau founded Karkar.

-The Cambridge History of Iran, vol. 3(2): The Seleucid, Parthian, and Sasanian Periods, ed. Ehsan Yarshater (NY: Cambridge UP, 1983), 765.